Washed-up seaweed caused by last year's freshwater releases

March 15, 2017

The Gulf seems to be safe this year from cyanobacteria, but Fort Myers Beach's sandy shores have recently shown the after-effects of the Lake Okeechobee releases.

In the last month, the beach's wrack line - the line of washed-up detritus left on the sand at high tide - has been laden with dead plant matter.

"All that nutrient loading that came in (last year) overwhelms the aquatic system," said Rae Ann Wessel, natural resources policy director for the Sanibel-Captiva Conservation Foundation. "Nature's go-to solution is to grow plants. With over-nutrification of the system, that's the adaptation."

It's known as red drift algae or a macro-algae bloom, but it's not the same phenomenon as red tide or cyanobacteria. Red drift algae is something you can actually see, and is washed up and dead seaweed. It's not harmful to people, but it is an after-effect of last year's excessive freshwater releases.

Last year's heavy rains in January and February began the high-volume freshwater releases from Lake Okeechobee. Laden with nitrogen and phosphorous, weather conditions created the perfect environment for toxic blue-green algae blooms that plagued the east coast. Although the same toxic blooms didn't reach Fort Myers Beach, Lee County was put on Governor Rick Scott's state of emergency list.

This year, however, the state is reaching drought-like conditions - and it's causing the Caloosahatchee River to have too much salinity.

"Last year was record rain," Wessel said. "Now we're in the polar opposite position."

The Caloosahatchee needs some freshwater, otherwise the saltwater of the Gulf creeps up into the river, and also starves the estuary of water, she said. Currently the Caloosahatchee system is experiencing more than 51 days of inadequate water.

"Last year was the wettest January in 80 years, November 2016 was the driest in 80 years," Wessel said. "We have these widely-swinging conditions. We've gone from extraordinary volumes of water coming into the estuary to being starved of water this year."

John Campbell, spokesman for the Army Corps of Engineers's Jacksonville District, said the state as a whole has been very dry since Hurricane Matthew in October.

This month, Lake Okeechobee has stayed at about 13.5 feet. Last year at this time, it was at 16.5 feet, he said.

"Last year we had a lot of rain to cause the lake to rise. we're in a different scenario," he said. "We've been doing small releases to Caloosahatchee through fall and winter, to prevent too much salinity in the estuary."

He said weather conditions right now are the opposite of last year, so the threat of the toxic variety of cyanobacteria blooms again this year are, right now, low.

"Last year the freshwater was too much and it upset the balance," Campbell said. "We're expecting continued dry conditions."

There is no dominant trend, wet or dry, in a one to three month outlook, he added. But wet season doesn't usually start up until May or June.

Despite the lack of algal blooms, tourism in Lee County has take a bit of a dip this year.Fort Myers Beach Town Council Member Anita Cereceda didn't have numbers on hand, but said she could feel the difference as a long-time business owner in Times Square.

"Traffic is down," she said.

And she's not the only one - the Tourist Development Council's reports back up her intuition.

Average occupancy rate was down by 3.9 percent, according to the January 2017 statistics from the TDC. That adds up to a 9.6 percent decrease in bed tax collection that month compared to January 2016, and a 2.8 percent decrease in travelers through RSW Airport. These reports cover the entirety of tourism in Lee County.